School of leadership aproaches and challenges: a study of international and portugueses school leaders in Portugal

O objectivo deste estudo qualitativo era investigar os estilos de liderança e os desafios com que se deparam os directores de escolas portuguesas e internacionais na área de Lisboa. A pesquisa é baseada em dados primários e secundários. Os dados secundários foram recolhidos a partir da bibliografia relevante para o tema. Os dados primários foram reunidos a partir de entrevistas pessoais com cinco directores de escolas públicas portuguesas e cinco directores de escolas internacionais. O guião para as entrevistas seguiu as quatro principais etapas sugeridas por Gillham (2000), e os resultados destas foram relacionados com a bibliografia sobre teorias e conceitos de liderança. A pesquisa mostra que há diferenças na forma como as escolas internacionais e portuguesas são geridas. As respostas dos participantes neste estudo confirmam o que é indicado na pesquisa. Os directores de escolas internacionais e públicas têm de enfrentar muitos desafios no seu quotidiano de gerir uma escola. A entrada em vigor de mudanças na escola, na organização do curriculum e a estabilidade são desafios comuns com que se deparam os directores tanto das escolas internacionais como das portuguesas. Contudo, o estudo demonstra que os líderes das escolas internacionais estão preocupados com as expectativas da administração, enquanto os directores das escolas portuguesas preferiam ter mais autonomia e menos burocracia. A literatura consultada sugere que um líder precisa de ter uma ampla variedade de características e a capacidade de as aplicar conforme a situação e as circunstâncias, e isso foi confirmado pelo estudo. As duas características pessoais identificadas por todos os participantes são ser uma figura presente na escola e a competência em ser um comunicador eficaz. Todos os participantes neste estudo foram capazes de identificar os seus pontos fortes e as áreas a melhorar. Todos os directores de escolas internacionais e portuguesas reconheceram que envolverem-se em demasiados projectos era a área a melhorar enquanto que ser assertivo foi identificado por todos os participantes como um ponto forte comum. A capacidade para reflectir e reconhecer estas duas áreas em si próprio foi identificada pela literatura consultada como essencial para uma liderança eficaz. Os resultados do estudo concluem que os directores de escola preferem um estilo de liderança democrático em ambos os casos, tanto nas escolas públicas como nas internacionais, e que autonomizar e apoiar os colaboradores para implementarem novas ideias são estratégias motivacionais.The purpose of this qualitative study was to investigate the leadership styles and challenges encountered by Portuguese and International school principals in the Lisbon area. The research is based on primary and secondary data. Secondary data was collected from the relevant literature. The primary data was collected via personal interviews with five Portuguese and five international school principals. The interview questionnaire followed the four main stages suggested by Gillham (2000), and the results of these were discussed to the literature on leadership theories and concepts. Research shows that there are differences on how international schools and Portuguese schools are governed. The answers from the participants of this study validate what is suggested in the research. International and public-school principals have to face many challenges in their day to day of running a school. The implementation of changes in the school, curriculum alignment and consistency are common challenges found by the international and Portuguese school principals. However, the study demonstrates that international school leaders are concerned with stakeholder’s expectations while Portuguese school principals would rather have more autonomy and less bureaucracy. The literature suggests that a leader needs to have a wide range of characteristics and the ability to apply them according to the situation and circumstances and this has been verified in the study. The two common personal traits identified by all participants are, being a present figure in the school and to be an effective communicator. All the participants in this study were able to identify personal strengths and areas for improvement. All international and Portuguese school principals recognised that getting involved in too many projects was the area of work they needed to improve whereas being assertive has been equally identified by all participants as a common strength. The ability to reflect and acknowledge these two personal areas has been suggested in the literature to be crucial in effective leadership. The findings conclude that school principals prefer a democratic leadership style in both scenarios, international and the Portuguese schools, and that empowerment and supporting staff to implement new ideas are motivational strategies

Anaerobic digestion of sludge from marine recirculation aquaculture systems

Trabalho de investigação desenvolvido na Delft University of TechnologyTese de Mestrado Integrado. Engenharia do Ambiente. Faculdade de Engenharia. Universidade do Porto. 201

Antioxidant activity and lipid peroxidation in Artemia nauplii enriched with a DHA-rich oil emulsion and the effect of adding an external antioxidant based on hydroxytyrosol

Artemia nauplii catabolise polyunsaturated fatty acids (PUFA); in particular, they retroconvert docosahexaenoic acid (DHA, 22:6n-3), so enrichment is a continuous quest towards increasing PUFA through the use of PUFA-rich enrichment products. However, optimal conditions during enrichment (aeration, illumination and temperatures around 28 ºC) tend to accelerate autoxidation of PUFA, and the formation of potentially toxic oxidation products. Water-soluble antioxidants like the polyphenolic compound hydroxytyrosol (3,4-dihydroxyphenylethanol), a polar molecule found in the water fraction resulting after the milling process of olives, arise as promising compounds to prevent oxidation during Artemia enrichments. We investigated the antioxidant activity and lipid peroxidation in Artemia nauplii during enrichment, and the effect of adding an external antioxidant based on hydroxytyrosol during the enrichment with a PUFA-rich emulsion (M70). For this purpose, the activity of antioxidant enzymes (catalase, superoxide dismutase, glutathione-S-transferase, glutathione peroxidase), as well as lipid peroxidation, were determined in enriched and unenriched Artemia nauplii. To validate antioxidant activity and lipid peroxidation, in a first experiment, nauplii were enriched with microalgae (Tetraselmis suecica), yeast (Saccharomyces cerevisiae) and M70 emulsion. In a second experiment, enrichment with a commercial emulsion (DC Super Selco), M70, and a combination of M70 and hydroxytyrosol (Hytolive, HYT) added as an external antioxidant was performed. The combination of M70 with HYT produced the best results, in terms of activity of antioxidant enzymes. The analysis of the fatty acids from total lipids showed that the addition of hydroxytyrosol preserved the DHA percentage of enriched nauplii